Mobile computing devices such as personal digital assistants, contemporary mobile telephones, and hand-held and pocket-sized computers are becoming important and popular user tools. In general, they have become small enough to be extremely convenient, while consuming less battery power, and at the same time have become capable of running more powerful applications.
During the process of manufacturing such devices, embedded operating system images are typically built into a monolithic image file and stored in non-volatile storage (e.g., NAND or NOR flash memory, a hard disk, or the like) of each device. As a result, the monolithic image file has to be preconfigured from the various parts that make up an operating system. Further, updating such a device is necessary or desirable from time-to-time, and requires making changes to the operating system.
However, there are a number of disadvantages when dealing with a monolithic image, including that to install any update, the entire image (or possibly some predefined subset thereof) needs to be replaced, which requires a large amount of resources including temporary storage and bandwidth. Monolithic replacements have heretofore been used for updating such devices, because updating separate components of the operating system is a difficult task, due to various conflicts and dependencies. Further, any such componentization leads to another problem, in that an initial image is still needed for manufacturing, but initial images heretofore were essentially just monolithic groups of bits transferred to devices. What is needed is a mechanism for converting operating system image components into a file system-based manufacturing image that is suitable for use as an initial image, yet is designed to facilitate componentized updating of the device.